Optical fiber has been established as the transmission medium of choice for telecommunications because it supports very high bandwidth over long distances and provides transmission speed capabilities that far exceed those of conventional copper-wire technology. Research is now looking at other possible applications for optical interconnect technology.
In one such application, free space optical interconnects are being researched as promising high speed communication platforms for the next generation of server systems, and may be used in smaller workstations and computer-to-computer parallel data-communication links in local area networks. For example, when utilized in server systems, free space optical interconnects will be utilized to support direct board-to-board communications within the server housing.
One of the key issues with free-space optical interconnects is that the boards that are to be interconnected are not rigidly coupled, and that their relative positions are likely to be time varying. Some server manufacturers require the ability to hot-swap boards in-situ without the use of any special alignment tools. Therefore, the successful implementation of free-space optical interconnects requires addressing this alignment issue.
A second potential application of free space optical interconnects involves optical data switching, which takes an output from one or more optical fibers and translates that light to other optical elements (e.g., MEMS mirrors, arrayed waveguides, and filter arrays). Again, the successful implementation of free-space optical interconnects in this application requires reliable alignment between the source and target elements.
What is needed is a free space optical interconnect system that automatically positions the emitters and/or detectors at power up, and monitors and adjusts the positions during operation.